Understanding Greater Everglades Mammal Communities within and adjacent to the Arthur R. Marshall Loxahatchee National Wildlife Refuge

Science Center Objects

WARC Researchers are using a variety of methods to assess mammal communities across the Greater Everglades.

Greater Everglades mammals

Common cotton rat outfitted with a radio telemetry transmitter, which allows WARC researchers to track the movement and survival of mammals in the Greater Everglades.

The Science Issue and Relevance:  The punctuated decline of mammal populations in the southern portion of the Greater Everglades over the last 20 years is expected to have a profound influence on the ecology of the system and the likelihood of successful ecosystem restoration. There is direct evidence that predation by the invasive Burmese python has caused these declines, and the extent of mammal declines are moving northward. Accordingly, for areas that have yet to see extensive python impacts (e.g., Arthur R. Marshall Loxahatchee National Wildlife Refuge), there is an urgent need to rigorously 1) quantify mammal communities, 2) understand the causes of mammal mortality, and 3) understand how changes in mammal populations might alter the health of the ecosystem.

Greater Everglades mammals

A remote camera captures mammals’ interactions with food resources and helps assess how quickly and how much of the carrion and fruit is removed.

Methodology for Addressing the Issue:  To help address these knowledge gaps, we are assessing mammal communities across the Greater Everglades using a variety of methods. Specialized cameras help us detect both large (e.g., white-tailed deer) and small mammals (e.g., rodents), and we conduct extensive searches to find signs and tracks of mammals. We then use these data to develop models to identify where mammal populations have changed and what mammals are most vulnerable to invasive pythons.  We also use radio telemetry, which lets us track the movement and survival of mammals - using the common cotton rat as our model species - in areas with extensive or minimal python activity. Finally, we are conducting experiments to better understand the important role mammals play in maintaining ecosystem heath. Carrion and native fruits have been placed in areas with various python activity. A remote camera captures the mammals’ interactions with the food resources and helps us assess how quickly and how much of the carrion and fruit is removed. This information will help us evaluate changes in mammals’ ability to remove carrion and disperse seeds and identify how the ecosystem might change as mammal populations change.

 

Future Steps:  We plan to expand our work to further understand the patterns of mammal loss and the implications for ecosystem health. Specifically, we will examine the use of new tools to find rare mammals and we will evaluate the use of advanced molecular techniques to understand how Burmese pythons may be competing with the region’s native mammalian predators.